Insert descriptions between the programme sounds
Rationale
The benefits of audio description will be reduced if it obscures speech or other important sounds. It should therefore be used only in the audible gaps, though not necessarily in every gap.
Directions and techniques
Avoid talking over dialogue or commentary
Avoid obscuring dialogue or commentary with audio description. This is sometimes referred to as one of the ‘golden rules’ of audio description. Since dialogue and commentary are important for understanding and enjoyment, obscuring them with description is generally counterproductive. However, due to time constraints it is not always possible to fit the required descriptions into the gaps between programme sounds. If it is more important for the listener to hear a particular description than to hear the dialogue, then dialogue may be sacrificed. This should be done carefully however and in a way that does not make it obvious that dialogue has been removed. It would be wrong to mute the dialogue mid-sentence because the viewer would then realise that dialogue has been removed and may wonder if they have missed something important.
Avoid obscuring other important sounds
It is not only the dialogue and audio description that provides the information. Background sounds like gunfire, shouting or a car pulling up can also convey vital information, so these must not be obscured by description.
Do not try to fill very short gaps between dialogue
If the gaps between dialogue or commentary are too short, the audio description may be more of a hindrance than a help.